Faulty-line-section cut-out



F. J. NAN KVELL FAULTY LINE SECTION CUTOUT Jan. 14, 1930.

Original Filed'Aug. 15, 1924 2 Sheets-Sheel 1 WITNESS Jan.`14, 1930. F. 1. NANKlvELl.

FAULT LINE SECTION CUT-OUT Original Filed Aug. l5

. 1924 2 Sheets-Sheet 2 d C 1 l l l -IJ L .o 2f 2 V n- 6 u V a a e A- lx n y 7 5| vnx al VA r l: 4l ao INVENTOR VJITNESS Patented Jan. 14, 1930 UNITED STATES FRANK J. NANKIVELL, 0F .NEW YORK, N. Y., ASSIGNOR T0 GENERAL ELECTRIC COM- PANY, A CORPORATION OF YORK FAULTY-LINE-SECTION CUT-OUT Application -led August 15, 1924, Serial No. 732,265. Renewed .Tuly 2, 1928.

In systems of electric distribution, it is customary to divide the service conductors into sections to which power is supplied from a central station by feeders. The feeders are connected tothe sections and to each other by seetionalizing switches, whereby any section of the feeders or distribution system may be connected or disconnected from the source, which becomesnecessary when a short-circuit occurs or repairs are to be made. These sectionalizing switches are manually 'operated and if a short-circuit occurs, dependence is placed upon an automatic overload switch, or circuit breaker, at the central station to open the circuit and prevent further damage.

The object of my invention is to provide means whereby a faulty section may be eut off from the central station as soon as the operator ,learns by the openingof the overload switch that trouble has occurred. This may be accomplished by the use of auxiliary circuits extending out from the central station and reaching all sectionalizing switches that it may be desired to operate, and relay apparatus located at each switch which is so co'nnected with the auxiliary circuit as to enable the operator to perform the following acts First, by manipulation of suitable switches in the auxiliary circuits at theccnt-ral station he can open all the sectionalizing switches. Second, by further manipulation of the switches in the auxiliary circuits, he can close these sectionalizing switches in suecession by power derived from ,the main circuit, so that upon closing his main line switch the sectionalizing switch nearest the central station will be closed first. This will bring about the closing of the next sectionalizing switch and so on until they are all closed up to the faulty section. Third, when such closing of the sectionalizing switches in sequence brings the faulty section in circuit and, therefore, again trips the main switch, a condition of circuits is established at the sectionalizing switch thus closing on the faulty section which will render dead the switch-closing means at that point. This being the case, it is only7 necessary with the aid of the auxiliary circuits to again open all the sectionalizing switches and allow them to automatically close again after the closing of the line switch to re-establish connection with all the sections on the station side of the faulty one. lVhen by the operation of the auxiliary circuits the exploration has discovered the faulty section and opened its sectionalizing switch, a signal device located at that point and in communication with a reception device at the central station enables the operator to determine at which section the trouble has occurred, so that steps may be immediately taken to remedy the fault.

The service conductors are sometimes arranged in the manner of a loop, so that all parts of the system in the loop may get power in more than one way. In such a case, when a fault occurs on any given section, it becomes necessary to open two seetionalizing switches, one oneither side of the fault, and in my present invention means are provided whereby the sectionalizing switch may be operated by power from either ofthe disconnected sections, relay connections being so arranged that whichever section is first ready to supply the power for the closing ofthe sectionalizing switch will render the other section inoperative during that particular operation of the switch and also will set up a state ot' affairs that will enable the operator by-repcating the manipulations of the auxiliary circuits to disconnect the other section switch and thus entirely isolate the faulty section.

The invention may be best understood by reference to the accon'ipanying drawing in which Figure l is a diagram showing the central station and a distribution system with my invention applied thereto.

Figure 2 is a sketch of a complete system of distribution showing the relation of the auxiliary circuit to the main circuit and the sectionalizing switches.

Figure-Sl is a perspective View of a mechanism for operating the sectionalizing switch.

Referring first to Figure 2, A represents a main distribution circuit having feeders in sections indicated by 1 to 9 with branches indicated by a to g, the location of the sectionalizing switches being B is an auxiliary circuit reaching to all the indicated by crosses.

lJO

sectionalizing switches and extending to the central station C.

Referring to Figure 1, the dot and dash line G indicates the central station in which is located a main line switch D, which in its closed .position is held closed by a latch E, the switch opening by gravity when tripped by overload relay F releasingthe latch E. The diagram illustrates a three-phase distribution system with a neutral wire. At Gis shown a sectionalizing switch. These sectionalizing switches are of the gravity type, that is to say, they are opened by dropping of their own weight when the mechanism that holds them closed is tripped. The switch is closed by an electric motor shown at M, which has a worm m operating on a worm wheel m", a pinion m2 and a rack ma, the rack being connected to the switch G so that when it is elevated, the switch is closed. A suitable tripping mechanisiu is shown and consists of a bell crank H, which inipinges on a pin h (see Figure 3) whereby the frame fm.,l that carries the pinion fm.-2 may be turned around on the shaft of the motor so as to force the pinion out of engagement with the rack, thus enabling the sectionalizing switch to drop of its own weight.

At each sectionalizing switch there is aV transformer connected with the line onA the side towards the central station (in case of a loop this will be on both sides) and this transformer, when energized, furnishes power for the operation of the motor M. These transformers are designated by Pot. l and Pot. 2,

. as shown in the drawings, as one furnishesv potential from the first section to cause the motor to :close the switch onto the second section and vice versa. There are also located at each sectionalizing switch current transformers indicated in the drawing by C. Ts, the purpose of which is to reproduce line current on a miniature scale and actuate the relay Re when the sectionalizing switch is closed against'a short circuit. It should be stated here that a characteristic of the sectionalizing switchesi`sfthat they-make an initial contact when thefswitch travels the dislance 'marked w, atwhich point, if there is ashort circuit on the next section, the overload main line switch in the central station will open the main line and become fully closed a short interval of time later whenthe motor M has carried the switch its complete travel indicated by y. In my present invention I take advantafve of this characteristic of secliolializing Swithe but in the brdi' aspects ot my invention any other feature that operates diierently in case of a short circuit maybe made use of. f

The essential thing to be noted here isthat ,..the motive mechanism operating the sectionalizing switch is adapted torst make an initial contact of the switch and then, unless otherwise interrupted, may continue 4its motion for a. short period of time after the initial Contact is made, at which time the switch may be said to be completely closed although in the broader aspects of my invention it would not be necessary for the switch itself to make further movement. i

will now describe the means whereby propose to discover and isolate a faulty section. To do this l may make use of auxiliary circuits 1, 2 and 3, which by means ot switches J in the central station may be connected with contacts a, l), c, and d that are in turn connected with a double pole switch K that will be used to connect the auxiliary circuits with a source ot power L. Each sectionalizing switch has attached to it three cams N, O and P operating respectively three switches c2, cs and c4 in such a way that when the scctioiializing switch is entirely open, cgis open, c3 is closed and c,L is open. When the switch makes Contact indicated by travel fr, c2 is closed, c3 is closed and ci is open, and when the switch is entirely closed, c2 is closed, c3 is open and c is closed. R1 to RG are relays. R1 operates to close a switch C1 when energized by the closure of switches .l on contacts a and c. 'When C1 is thus closed R5, by the closure of switch J on'contacts a and d, can be made to break c5 and close c6, which, if the main line has current, will cause the motor M to operate to close the sectionalizing switch. Relay R2 is for the purpose ot tripping the motor-operated mechanism previously described, by impinging against the arm ofthe bell crank H. A dash pot S, the piston of which is connected to the bell crank, will prevent the quick return of the tripping mechanism, so as to give time for the switch to open entirely. A s ring T is shown as a means for bringing t e gearing back into mesh. Relays RS and R4 arev for the purpose of acting vas mutual cut-outs, each for the 'other so that whichever operates first the other will be incapacitated. This is for thereason that it is desired to have only the potential transformer on one side of the sectionalizing switch, in case power is coming from both sides, to operate at a time. A time element is necessary for these relays and is furnished byv the dash pots U, which cause these relays .to operate slowl when energized and have a uick return w en deenergized. Relay Re is or the purpose o opening contact C1 which will cause the interruption of the motor circuit by breaking 'c6 and this will happen when RB is energized by the C. Ts. on y in case there is a short on the next succeeding section. 1f there' is noshort on the At W is shown another cam attached to the sectionalizing mechanism that operates to break the circuit of Pot. 1 and Pot. 2 when the sectionalizing switch is entirely closed. This should open the switches w1 and Q02 immediately after cam O opens c3. lBy opening these circuits, which are connected with the power lines, safety in regard to overheating and in advertent operation is attained.

A clearer understanding of the functions of the mechanism thus far described will be obtained from the following description lNhcn the station operator has a shortcircuit on a feeder and finds that he cannot keep his line switch closed, he closes his double-pole, single-throw knife switch to put power on his control wires.` He then closes the contacts a, b, c and d in the following sequence:

. a and c.

b and ci and closes line switch.

a and (Z (short will open switch again). o and d and closes line switch.

. a and Z (short will open switch again). b and d and closes line switch.

i. a and d (injured section will be cut off and thel restlof the feeder will be inservice again). The operator may then open `his double-pole single-throw knife switch and so remove the power' from his control lines.

The cycle of operation at the disconnect will he as follows:

On making contacts ci and c-power from the station switchboard will actuate R'l and make contact C1.

On 4making contacts o and d-power from the station switchboard will pass through c2, which will be closed when the sectionalizing switch is closed and will actuate Rg. This will trip the switch opening release and allow the sectionalizing switch to fall out. The slow return element or dash pot S will insure the complete opening of the sectionalizing switch. As the sectionalizing switch opens, the cams. will open contacts c2 and c4 and close contact c3. All sectionalizing switches on the control circuit will be opened by this operation.

rlhe operator will then close his line switch again. 1f the fault or short-circuit is on the first section of the feeder, the line switch will trip out once more, indicating that the trouble is ou the first section. If the first section is in good shape. the power will stay on that first section. Assuming the powerl to energize the right hand side of the diagrani, lot. l will deliver power tolti, through 0.,. It, will act to open cT and close ci.. yl`he opening of c, prevents the `operating of l?. when thc primary side of Pot. 2 becomes energized. The closing of cg energizes the motor circuit. lf the power energizes the `left-hand side of the diagram, Pot. 2 will deliver power to R., through c7. R, will act to open c., and close 0,0. The opening ofc,n

prevents the operating of R3 when the primary side of Pot. 1 becomes energized. The closing of 010 energizes the motor circuit. In other words, no matter which side of the disconnect receives power irst, the potential transformer on that side willcut out the potential transformer on the other side and supply current for :operating the motor. In the remote possibility of the power coming on both sides of the disconnect at the same instant, the quicker of the two relays 3 or 4 willcut out the potential transformer on the opposite side and supply the motor with current.

On making contacts a and cZ-power from the station switchboard will pass through C1 and actuate R5, which willopen c5 and Vclose c6. The closing of cG completes the motor circuit and the motor M will start to run on power from one or other of the potcntial transformers and close the sectionalizing switch. If the fault or short-circuit is on the second section of the feeder, the fact will make itself known as soon as the switch has traveled a distance (which is the travel necessary 4to make initial contact of the sectionalizing switch). Short-circuit current will flow through line and will cause RG to open C1. Opening C1 will cut olf the control power from R5, which will open c.; and stop the motor, then close cf, and shunt R6, thus preventing its becoming injured by overheating. Following this, the line switch in the station will trip out again, and indicate to the operator that he has encountered the trouble and that he can only supply power to his first section without making repairs. He must then open his sectionalizing switches once more by making contacts b and CZ and close his line switch on the first section. Ifthe second section is in good shape, the motor will carry the switch the complete distance y. Upon completing its travel O will open c3 and so stop the motor while P will close c., and so shunt Re, thus preventing it from opening C1 when the fault is uncovered on some subsequent section. As soon as the first sectionalizing switch is closed without encountering the fault, the second sectionalizing switch will start to close as a result of the power supplied to the next potential transformer. It is to be observed that contacts a and Z are to be left closed until the fault is located. Upon the closing of the second sectionalizing switch, the third will close and so on until the section where the fault is located is reached. Upon reaching the fault, R., on the last. closed sectionalizing switch will trip and open C1. Since all the disconnects on the station side of the last closed sectionalizing switch will have made the complete travel y. their contacts c4 will he closed, preif'enting their relays Rn from operating. 1n other words, only the RG on the sectionalizing switch which has not yet traveled beyond the distance Will operate. Here the line switch at the station will trip out and indicate to the operator that he has encountered the fault.

Contacts b and d must now be made again to open up all the sectionalizing switches once more. Y Y

The operator will then close his line switch again. l

Upon closing contacts a and d the second time, all the sectionalizing switches will close, one after the other, up to the one which has encountered the fault. Y This cannot close because its contact G1 is open.

If the feeder is of the loop type, the cycle of events will travel out from the station on all the sections and branches so long as the power stays on the feeder to operate the motors. The first branch to encounter the fault will cause the power to be cut off by tripping the line switch. At the same time it will prevent the sectionalizing switch on that section from operating to close a second time until the contacts a and vc are made to reset the contact C1. .lVhen the line switch opens up after the firsttrial, the operator has Alocated one end of the faulty section but he has yet to locate the other end. Upon making the contacts a and d for the second time the sectionalizing switch which has first encountered the fault cannnot close again as noted, but the sectionalizing switch on the other end of the faulty section which has not had a chance to close and trip its relay R6 because the power was interrupted by the tripping of the station line switch, will now come in contact with the fault and repeat the cycle of the sectionalizing switch on the first end. Its C1 will be opened by its Re and the station switch will trip for the second time.

Again the operator will have to make. contacts b and d to open up all the sectionahzing I switches.

and send a repair gang out to find and clear it' PWhile this description applies to a threephase, four wire loop feeder, modifications can be made to make it fit other conditions. If the feeder is not looped, only y'one potential transformer will be necessary. This is to be placed on the station side of the sectionalizing switch. Also it follows that no relay will be required to supply the necessary power to the motor from this potential transformer. In combinations of loops and branches, the sectionalizing switches on the looped sections will need two potential transformers and the ator branches will require only one. In some cases only two control wires will be necessary as the neutral of the feeder maybe used. Single-l ,A

phase operation will merely'be a simplilication of the threehase. Direct current feeders will require t 1e use of shunts in place of the current transformers and possibly resistances in place of potential transformers. The tripping and closing mechanism may bel any of the devices used for that purpose. A segmental gear may be used in place of the rack and the cams may be in a variety of forms, or even dispensed with altogether. In this latter case, electrical contacts will have to be placed directly on the mechanism.

An additional wire 4 will enable the operator, by closing switch J1 on contact er connected to a signal receiving device such as a battery .I2 and telephone .Lito receive the signal from the apparatus X, which may be a buzzer having a certain note, or any code signal device. The buzzer is brought into operation when C1 is opened as'it then closes on contacts X1 as C1 willonly be open and X1 closed at the sectionalizing switch which leads to the faulty section. The information thus obtained will enable the operator to save considerable time in directing the repair man to the location of the fault.

Assume now that the operator has just been through the operations of closing his sectionalizing switches for the rst time and has had his station switch open up and indicate that as the switches yclosed one after another, one came in contact with the troubled section. In coming in contact with the troubled section, the C Ts would cause RG to trip and open C1 and close the newcontact. With this contact closed the station operator can close his switches 'al and e and listen to his telephone receiver. Current from the battery will circulate through control wires 3 and 4, the buzzer, and the receiver. The buzzer in interrupting the circuit periodically at a predetermined frequencyl will give out a distinct tone that the operator can recognize as belonging to a certain definite sectionalizing switch.

After recognizing one switch, the operator can proceed with his work of opening the switches and closing them again. When the station switch opens a second time after the operator has begun sectionalizing, the operwill know that he has encountered the other end of his troubled section. He can then listen-again to his receiver and will be able to hear two buzzers working. By the difference in tone or frequency he can determine the second switch location. Then hc can proceed to tell the trouble man where to look for the trouble. The action of the buzzer will further be a check on the proper return, or if D. C. current is used on the control circuits with polarized relays and a switch at the central station for sending a D. C. current over the control wires first in one direction and then in the other. The latter alternative is shown in Figure l in dotted lines in connection with wires 3 and 4, Z and Z1 being the polarized relays, the relay Z being adapted to operate in connection with c2 and R2 and the relay Z1 being adapted to operate in connection with C71 and R5. There will in this case, of course, be a reversing switch as shown at Z3 -in the central station connected on the one side with a source of direct current and on the other side with wires 3 and 4. When D. C. control current is used, the battery J 2 may be omitted .and the signal sent out by apparatus X ma be transmitted to the receiving device by induction through repeater coils X2 and J4. It may even be desirable to omit R1 and reset el by hand since a trouble man must visit the. location of the fault before the sectionalizing switches connected to the faulty section can be again closed. In this case still another control wire may be omitted.

While I have described a preferred embodi- Y ment of my invention, it will be understood that there are many other ways of carrying out-'the invention and in my' copending application Serial No. 20,133, filed April 2, Y1925,

an alternative method is therein shown and Claimed which is to be understood as coming within the scope of the broader claims f herein made.

vTo those skilled in the art it will be apparent that I have disclosed a system for automatically exploring an electrical distribution system in such a way as to discover and automatically cut out a faulty section.

I claim:

1. The combination comprising a source of power, distributing conductors divided in sections, sectionalizing switches connecting said sections in series, a switch connecting the distributing conductors to the source 'of power and adapted to open the circuit in the event of overload, means for opening all the sectionalizing switches, means for closing the sectionalizing switches in succession commencing with the one nearest the central station, means at each sectionalizing switch operating when the said Switch closes on a faulty section, to lock out the said switch against subsequent reclosure so that upon repeating the opening and the successive closing of the sectionalizing switches, the fault-yV section will remain cut out.

2. A combination according to claim l in which the power to close the sectionalizing switch is supplied from the mainline.

3. The combination comprising an electri cal distribution system having sections with sectionalizing switches between them, a central station, a switch at the central station connected to the distributing system and adapted to open the circuitof'said system in the event of overload, means controlled from the central station for simultaneously opening all of the sectionalizing switches, and means for causingv them to close in succession by power supplied from the main line, the power from one side of the switch operating the switch to put power on the other side.

4. A combination according to claim 3 in which a loop system of distributing conductors is used with means for making operative connection with a section on one side ot' the sectionalizing switch while preventing operatve connection with the section on 'the other s1 e. l

5. The combination comprising an electrical distribution s stem having sections with scctionalizing switches between them, a central station, a switch at the central station connected to the distributing system and adapted to open the circuit of said system in the event of overload, means controlled from the central station for simultaneously opening all of the sectionalizing switches, andmeans for causing them to close in succession by a switch closing motor, operatable by current from either side of the switch, with imeans for preventing its operation from one side when it has been started from the other side.

6. In a system of electrical distribution supplied with power through an overload circuit breaker and having a plurality of sections. sectionalizing switches for disconnecting such sections from adjacent sections, motive mechanism for said switches adapted to cause the switch to make an initial contact and upon further movement to cause the switch to become completely closed and means for ditferentiating between a sectionalizing switch making initial contact and one completely closing.

7. In a system of electrical distribution having a plurality ot sections connected in series, sectionalizing switches for disconnecting such sections, auxiliary switch control circuits extending' to the sectionalizing switches, means operatable from one of such auxiliary circuits to cause the opening ot all the said switches, and means operatable from another of said auxiliary circuits to cause the closing of said 'switches one after'the other beginning with the one nearest the central station.

8. In combination, an electric circuit comprising a plurality of sections and sectionalizing switches connecting said sections in series, a source of current, an overload circuit breaker between said source and said circuit, means for effecting the opening of all of thc sectionalizing switches between the faulty section and the overload circuit breaker when a fault occurs on any section, and means associated with each sectionalizing switchA for effecting the closing thereof when the adf sections, means associated with each switch for reclosing it 1n response to the energiza` jacent section nearer the source is energized and forlocking it out against a subsequent. reclosure whenever it is reclosed at a time when there is an overload connected to the other adjacent section.

9. In combination, an electric circuit comprising a plurality of sections and sectionalizing switches connecting said sections 1n series, a source of current, an overload circuit.`

has been opened by a fault on any one of said tion of the adjacent section nearer said source, and means associated with each switch and responsive to a predetermined abnormal elec-v trical condition of rendering the associated reclosing'means inoperative to eiect a subsequent reclosure thereof when said predetermined abnormal electrical condition occurs within a predetermined time after any reclosure.

10. In combination, an electric circuit comprising a plurality of sections and sectionalizing switches connecting said sections in series, a source of current, an overload circuit breaker connecting'said source to one of the end sections of said circuit, means Jfor effecting the opening of all of the sectionalizing switches between the faulty section and said overload circuitbreaker after said circuit has been opened by a fault on any one of said sections, means associated with each switch for reclosing it in response to the.

energization of the adjacent section nearer said source, means associated with each switch and responsive to the current therethrough'for rendering its associated reclosing means inoperative to eiect a subsequent reclosure thereof when the current through the associated switch exceeds a predetermined value, and means controlled by each switchfor rendering the associated current responsive means inoperative to prevent further reclosures of the switch after it has remained closed for a predetermined time.

11. In combination, an electric circuit comprisingA a group of series connected sections with a sectionalizing switch between each two adjacent sections, means for effecting the opening of all of said switches, means associated with each switch for reclosing it when an adjacent section is energized, lockout j means responsive to a predetermined electrical condition of anfadjacent section for rendering each reclosingmeans inoperative to eiect asubsequent reclosure of the associated Vswitch whenever it is reclosed and there is a fault on the adjacent section, and means controlled by each' switch for rendering its associated lockout means unresponsive to said an adjacent section for.

' switch in response predetermined electricalcondition after the switch has remained closed for a predetermined time.

12. In combination, two electric circuits,

a switch connecting said circuits, automatic recloslng means for said switch, a relay responsive to a predetermined abnormal electrical condition on one of said circuits for controlling said reclosing means in a predetermined mannei, and means controlled by the position of said switch for rendering said relay unresponsive to said predetermined abnormal condition after said circuits have remained connected together for a predetermined time.

13. In combination, two electric circuits, a Aswitch connecting lsaid circuits, automatic reclosing means for said switch, an overcur-` rent relay for controlling-said reclosing means in response to the current through said switch when closed, and means controlled by said. switch for rendering said overcurrent relay inoperative to control the operation of said to the current through said switch after said circuits have been connected together for a predetermined time.

14; In combination, two electric circuits, a switch connecting said circuits, automatic reclosing means -for said switch, a current transformer having its primary'connected in series with one of said circuits, an overcurrent relay connected to the secondary of said current transformer and controlling the operation of said reclosing means, and means controlled by the Iposition of said switch for short-circuiting said relay after said circuits have remained connected together for a predetermined time.

prising a plurality of sections'connected in.

series by sectionalizing switches, means for supplying current to each of the two end sections of said circuit, an overload circuit breaker between each end section of said circuit and the means for supplying current thereto, means for eii'ecting the opening all of said sectionalizing switches after a fault on a section has opened both of saidoverload circuit breakers, and means associated with ea'ch switch for reclosing it in response to the energization of either of its adjacent sections and for locking it out against a subsequent reclosure whenever it is reclosed at a time when there is a fault on the adjacent section.

16. In combination, an electric circuit comprising a plurality of sections connected in series by sectionalizing switches, means for supplying current to each of the two end sections of said circuit, an overload circuit breaker between each end section of said circuit and the means for supplying current thereto,

Ameans for effecting the opening all of said switch for reclosing it in response to the energization of either of its adjacent sections, and means associated with each switch and responsive to a, predetermined abnormal electri-l cal condition on an adjacent section for rendering the associated reclosing means inoperative to,rec1ose the switch when said predetermined abnormal condition voccurs within a predetermined time after the switch has connected the adjacent sections together.

FRANK J. NAN KIVELL.

soy 

